A Scalable Application Architecture for composing News Portals on the Internet Serpil TOK, Zeki BAYRAM. Eastern MediterraneanUniversity Famagusta Turkish Republic of Northern Cyprus

Overview Using WEB services to provide content for news portals Tool for uploading content to each WEB service independently Web Application (News Portal) that queries Web Services based upon the user’s preferences and presents customized content Implemented in Microsoft .NET framework Not a new idea in itself, rather an application of existing technology to a real-world situation If developed further, could be the basis of customizable news portals

XML Web Services A kind of remote procedure call Allows the composition of applications from components that are physically in different locations on the Internet Generally use SOAP (Simple Object Access Protocol) for communication with clients. Others are HTTP GET and HTTP POST Extends distributed computing to a broad range of client applications. With proper tools, very easy to design and use.

Components of the project A News Portal Site, implemented as an Asp.Net Web application A Windows Application for reporters, used to upload content to a Web service XML Web Services which expose news content to portals through a well-specified interface DBMS ( Ms SQL Server 2000) to store news content

The Architecture of the Project Newsportal WebSite (.aspx) XML Web Service (.asmx) XML Web Service (.asmx) Database1 Database 2 Windows Application for Reporter (.cs) Reporter provides news Reporter provides news Internet User

Uploading news to a news Web Service Using the Windows application, each reporter can Compose and edit a news item Upload his news item to his dedicated database Manipulate the contents of his database, for example, see a listing of articles, remove articles, modify articles Rudimentary tool, designed as a proof of concept

Screen-shot of the Windows application

The NewsPortal Web Application This is the “front end” for end consumers of the news provided by reporters The idea is that many others with different user interfaces but using the same data sources will be made available to users. Customized content In the sample portal, A user can see the most recent news of reporters covered by the portal, A user can search for articles in the site By reporter name, By category, By a date, By a Date Interval, By a keyword or sentence in subject, Or , a user can see all reporters’ articles without any restrictions,

Screen-shot of the Entry page of the News Portal

Main Search Form of the Sample Portal

Web Services Provided

Description of the Web Service functions Takenews( ) WebMethod: Returns the most recent articles by the authors. Takereport( string no, string fname) WebMethod: This function takes two parameters: an article ID (“no”), and an author name (“fname”). It returns the article belonging to the author, and which has the specified ID (used mainly for testing purposes) Takesearch (string q) WebMethod: This is the most general of the Web methods: it takes a query string (whose format should naturally be known to the calling program) containing complex search criteria, and returns all articles satisfying the criteria. In a production version of the application, this would be left out! (to be replaced by more specific Web methods)

Microsoft .NET Framework An advanced multi-language platform for software development Huge library consisting of thousands of classes Visual tools for integrated program development and testing (Visual Studio.NET) Support for desktop applications (Windows Forms), Web applications (Web forms, ASP.NET), Database access (ADO.NET), XML Web Services

Web Forms and ASP.NET Used for the server-side part of a WEB application Develop WEB applications as if developing desktop application UI components placed on a form, and event handlers written for components Components translated into HTML components automatically Some functionality delegated to the client side through the automatic generation of scripting code to be executed on the browser (validity checking of input etc.)

Web Forms and ASP.NET The transfer of the page to a remote browser not too important from a programming point of view Separation of the user interface and the logic of the application (the so-called “code behind” approach) Compiled .Net-based environment

Web Services using the .NET framework Web service defined by extending a class available in the .Net framework Using web services involves adding a Web reference to your project, which automatically creates a local “proxy class” for the service. Any interaction with the Web service goes through the methods of the proxy class

Future Work More comprehensive Web services (larger assortment of functions) Subscription mechanism for Web services (only those portals who subscribe to be allowed to obtain their revices)

Conclusion We presented a prototype application that uses Web services and a multi-layered architecture to supply content for news portals Our architecture is extendible (just add more Web services) and leads to easy building of customized content for end-users We briefly described the advantages of using an advanced programming platform for implementing a project such as this